A mobile terminal which is a portable type computer has been developed. This mobile terminal displays a plurality of icons, which can be selected by a user, on a display section. The user operates an operation section to select a desired icon from among the plurality of icons displayed on the display section. The mobile terminal displays the contents of the selected icon on the display section.
In recent years, the mobile terminal for which a touch panel of a capacitance type is provided instead of the display section has been developed. In the mobile terminal, the user can select a desired icon from among a plurality of icons by touching the touch panel with a finger. Because the mobile terminal has been miniaturized, the size of the touch panel which is provided for the mobile terminal is restrained. On the other hand, if the icons to be displayed once on the touch panel increase more, the user can select the desired icon the less number of times.
Also, when the touch panel of the capacitance type is provided for the mobile terminal, a plurality of transparent electrodes of linear sensors and so on are arranged on the touch panel in the pitch of about 5 mm. In this case, the mobile terminal detects the capacitance values of the capacitances formed between the plurality of transparent electrodes and the finger when the finger touches the touch panel, and estimates the position of the finger. Therefore, it is difficult to specify the position of the finger on the touch panel and it is easy to cause an error. Thus, it is different from a method of selecting a position with a mouse, a stylus pen and so on. Also, a range of the icons on the panel which the can be selected through the touch is a part or its periphery of the displayed icon in many cases. When the displayed icon is small, it is difficult for the user to right select the icon.
Moreover, when the touch panel of the capacitance type is provided for the mobile terminal, it is general that the touch panel is touched with not a stylus pen but the finger. If the displayed icon is small, when the user tries to touch the touch panel, the desired icon can be concealed with the other fingers so that the desired icon can not be confirmed.
To prevent this problem, a technique which an object icon is displayed in an expanded state is described in JP 2009-86612A. In this technique, there is no detailed description of the position of an operation instructing section and a distance between a touch panel and of the operation instructing section. However, when the operation instructing section approaches the touch panel, the object icon of the plurality of icons which is displayed on the touch panel is displayed in an expansion state based on a capacitance value between the operation instructing section and the touch panel. Because the object icon is displayed in the expansion state when the operation instructing section approaches the touch panel, the improvement of operability can be attempted to the user and the user can handle it easily.
However, regardless of detecting a capacitance value between the operation instructing section and the touch panel, the operation instructing section may be a touch pen (a stylus pen) in addition to the finger. Therefore, when an object which is not the finger and the touch pen (such as a needle, a sharp pen, a ball-point pen, . . . ) approaches the touch panel, the object icon of the plurality of icons displayed on the touch panel is displayed in an expansion state based on the capacitance value between the object and the touch panel. In this case, there is a case that the icon which is not the object is displayed in the expansion state, and the operability is improved to the user.
As another technique, in JP 2006-236143A, a distance between a finger of a user and a touch panel is determined from an image showing a main display section (the touch panel) and its neighborhood and taken by a camera. When the distance is a predetermined distance, an icon is displayed on the touch panel in the expansion state. However, this technique needs the space where the camera is arranged.
Also, another technique is described in JP H08-212005A and JP H11-065769A, in which a distance detection mechanism emitting light is arranged around the touch panel. For example, when the light is interrupted at a position near the touch panel after light is interrupted at a position far from the touch panel, an icon is displayed on the touch panel in an expansion state. However, in this technique, because the distance detection mechanism is arranged around the touch panel, the depth would be provided to the touch panel.
Also, another technique is described in JP 2007-004660A and JP H05-046308a, in which an icon and a key are displayed in the expansion state in a size according to the size of a finger when the finger touches a touch panel.